1. Field of the Invention
My invention relates to hand tools for deburring the inner and outer edges of the cut end of a tube of the like.
2. Description of the Prior Art
In the use of EMT-type conduit for electrical wiring installation, the cutting of the tubing causes burrs or ridges to be formed at the cut end. Some electrical codes forbid the use of a roller-type tube cutter, and the electrician will generally utilize a hand hacksaw for cutting conduit to a required length. This technique causes formation of sharp burrs on both the inner and outer edges of the cut end. Such burrs must be removed to allow fitting of the conduit into couplings or other fittings, and to prevent damage to electrical wiring insulation that is subsequently pulled through the conduit.
The deburring operation is commonly performed by the electrician with makeshift means, such as using the handle of a pair of slipjoint-type pliers to ream the inner edge and the jaws of the pliers to clean the outer edge. While the prior art has provided specialized tools that can perform this operation more efficiently, these tools have been relatively complex and expensive. For example, F. R. Wilson in U.S. Pat. No. 3,232,145 teaches a hand reamer having the capability to deburr both inner and outer surfaces of the cut end of a tube. However, one surface at a time must be reamed or champfered, requiring two operations. A tool capable of concurrently reaming the inner edge of a cut tube and champfering the outer edge is described by R. V. Strybel in U.S. Pat. No. 3,870,432. This tool is relatively complicated, involving a plurality of cutter blades, springs for maintaining the blades engaged with the cut end of the tube, and interchangeable guides for various tube sizes.